Web/API/ProgressEvent/ProgressEvent

The ProgressEvent() constructor returns a newly created ProgressEvent, representing the current completion of a long process.

Syntax

progressEvent = new ProgressEvent(type, {lengthComputable: aBooleanValue, loaded: aNumber, total: aNumber});

The ProgressEvent() constructor also inherits arguments from Event().

type: Is a DOMString representing the name of the type of the ProgressEvent. It is case-sensitive.
lengthComputable Optional: Is a Boolean flag indicating if the total work to be done, and the amount of work already done, by the underlying process is calculable. In other words, it tells if the progress is measurable or not. It defaults to false.
loaded Optional: Is an unsigned long long representing the amount of work already performed by the underlying process. The ratio of work done can be calculated with the property and ProgressEvent.total. When downloading a resource using HTTP, this only represent the part of the content itself, not headers and other overhead. It defaults to 0.
total Optional: Is an unsigned long long representing the total amount of work that the underlying process is in the progress of performing. When downloading a resource using HTTP, this only represent the content itself, not headers and other overhead. It defaults to 0.

Specification	Status	Comment
XMLHttpRequestThe definition of 'ProgressEvent()' in that specification.	Living Standard

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`ProgressEvent()` constructor	Chrome Full support Yes	Edge Full support ≤79	Firefox Full support 22	IE No support No	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support 22	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes